Make PlatformFileForTransit a class on Windows.

components/nacl/renderer/ppb_nacl_private_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/nacl/renderer/ppb_nacl_private.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <numeric>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/containers/scoped_ptr_hash_map.h"
 #include "base/cpu.h"
 #include "base/files/file.h"
 #include "base/json/json_reader.h"
 #include "base/lazy_instance.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/macros.h"
+#include "base/process/process_handle.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "base/thread_task_runner_handle.h"
 #include "build/build_config.h"
 #include "components/nacl/common/nacl_host_messages.h"
 #include "components/nacl/common/nacl_messages.h"
 #include "components/nacl/common/nacl_nonsfi_util.h"
 #include "components/nacl/common/nacl_switches.h"
 #include "components/nacl/common/nacl_types.h"
@@ skipping 429 matching lines @@
       }
     }
   }
 
   IPC::PlatformFileForTransit nexe_for_transit =
       IPC::InvalidPlatformFileForTransit();
 #if defined(OS_POSIX)
   if (nexe_file_info->handle != PP_kInvalidFileHandle)
     nexe_for_transit = base::FileDescriptor(nexe_file_info->handle, true);
 #elif defined(OS_WIN)
   // Duplicate the handle on the browser side instead of the renderer.

[Mark Seaborn, 2016/03/29 19:24:09]

This comment doesn't apply any more, since you're removing the DuplicateHandle()
call in components/nacl/browser/nacl_host_message_filter.cc, so can you remove
it?

I assume the new code path handles renderer -> browser transfers securely?

[erikchen, 2016/03/29 20:57:42]

Removed the comment. Yes, the new path is secure.

   // This is because BrokerGetFileForProcess isn't part of content/public, and
   // it's simpler to do the duplication in the browser anyway.
-  nexe_for_transit = nexe_file_info->handle;
+  nexe_for_transit = IPC::PlatformFileForTransit(nexe_file_info->handle,
+                                                 base::GetCurrentProcId());
 #else
 # error Unsupported target platform.
 #endif
 
   std::string error_message_string;
   NaClLaunchResult launch_result;
   if (!sender->Send(new NaClHostMsg_LaunchNaCl(
           NaClLaunchParams(
               instance_info.url.spec(),
               nexe_for_transit,
@@ skipping 1279 matching lines @@
   // Mark the request as requesting a PNaCl bitcode file,
   // so that component updater can detect this user action.
   url_request.addHTTPHeaderField(
       blink::WebString::fromUTF8("Accept"),
       blink::WebString::fromUTF8("application/x-pnacl, */*"));
   url_request.setRequestContext(blink::WebURLRequest::RequestContextObject);
   downloader->Load(url_request);
 }
 
 }  // namespace nacl